The present invention relates generally to an electrical connector and, more particularly, to a high density, pressure contact type of electrical connector.
With an increasing input/output count for removable computer modules, the limits of present day pin and socket connector technology is being approached. The bulk associated with fitting a pin contact into the bore of a socket contact for mating connectors reaches practical limits in scale particularly where contact count extends into the thousands. One concept for extending total contact count and increasing density of the contacts in a connector is through the use of a "bed of nails" type of connector which is normally clamped between a pair of printed circuit boards, with the array of "nails" or contacts of the connector engaging a corresponding array of conductive pads on the two boards. Such "bed of nails" type of connectors which have been previously used have had the disadvantage that the contacts are straight and, therefore, have virtually no resilience that can accommodate for irregularities in the surface of the printed circuit boards engaged by the connector, and for connector manufacturing tolerances. Further, such prior art connectors have had problems in the precise spacial alignment and the positioning of the contacts therein.
U.S. Pat. No. 4,634,199 to Anhalt et al., assigned to the assignee of the present application, discloses a connector for making connections in a thin space between a pair of printed circuit boards. In contrast to a "bed of nails" type of connector in which there is an array of contacts distributed within a connector body, in the Anhalt et al. connector the contacts are arranged in two close straight rows and, therefore, are not suitable for making a multiplicity of electrical connections over a wide area as is required for use with computer modules having arrays of conductive pads thereon. The aforementioned Anhalt et al. patent discloses the use of contacts which are somewhat similar to those taught in the present application in that each contact has aligned, generally vertically extending contacting end portions, and a middle, generally V-shaped resilient portion, which allows the ends of the contacts to deflect inwardly against a resilient bias due to flexing of the V-shaped portion of the contact.
Connectors and relays are also known in the art which utilize a stack of insulators between which contacts are mounted. However, in such products, the contacts are not deflected axially, such as is desired for a "bed of nails" type of connector for clamping between a pair of printed circuit boards. Examples of connectors and relays of this type are disclosed in French Pat. Nos. 1,134,588 and 2,254,126 and Swedish Pat. No. 164,684.
It is the object of the present invention to provide a "bed of nails" type of electrical connector in which the contacts may be arranged in a high density with an arrangement which allows for increased contact flexure which will accommodate for irregularities in the printed circuit boards connected by the connector, and for connector manufacturing tolerances. Another object of the invention is to provide such a connector utilizing identical insulative strips which can be arranged and assembled to provide precise spacial alignment of the contacts, and staggering of the contacts which permits closer spacing of the contacts.